DuMSE: Toward Practical and Dynamic Multiuser Search Over Encrypted Cloud Data Against Keyword Guessing Attack

Abstract

For multiuser search scenarios over encrypted cloud data, the multiuser searchable encryption (MUSE) technology is a viable solution for incorporating privacy protection and favorable operability functions together. However, current MUSE technologies suffer from three practical limitations: 1) a secure channel between data owner and users will greatly increase the burden of owner; 2) a trusted third party (TTP) is required in some solutions; and 3) some solutions cannot resist keyword guessing attack (KGA), which means that the information of search trapdoor is easily leaked. In order to solve the above three problems, our first practical solution (DuMSE) without secure channel and without TTP is proposed in this article, which also can resist KGA. With inverted indexes, the search time complexity of DuMSE can be reduced to <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$r$ </tex-math></inline-formula> , where <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$r$ </tex-math></inline-formula> is the number of corresponding data. To support dynamically updating data, our second dynamic solution based on DuMSE is also proposed in this article, named as dynamic DuMSE (dDuMSE). The construction of dDuMSE includes not only the above features of DuMSE but also a new feature. Our analysis and experimental results show that the proposed schemes are secure and practical.